https://www.urbandictionary.com/define.php?term=redrum
red rum
murder spelled backwards, normally written on a wall in murder scenes, also red rum is blood
dumbass: whats red rum?
smart person: its the backwards spelling of what im gonna do to you!
Amityville horror Red Room
ake the ‘red room’, for example — a small, red painted room, around 4ft-by-5ft, that George Lutz discovered behind shelving in the basement.
https://www.dailymail.co.uk/news/article-2300807/The-Amityville-horror-The-boy-lived-true-life-haunted-house-breaks-40-year-silence.html
The room was not mentioned in the building plans and the Lutz’s labrador cross, Harry, refused to go near it, cowering in fear. But previous tenants insisted it had simply been used for storage.